Figure 2. Pre-mRNA transcribed from the Bmdsx mini gene is sex-specifically spliced. (A) The diagram shows the structure of the Bmdsx minigene. Open boxes: common exons. Shaded boxes: female-specific exons. Arrows: primers for PCR. (B) Poly (A)+RNA was extracted from the fat body of transgenic silkworms. These RNAs were reverse-transcribed with random hexamer, and the cDNAs were PCR-amplified with primers TGM2F and TGM2R. Resulting products were separated on a 1% agarose gel and visualized with SYBR Green I (Molecular Probes) at a dilution of 1: 10,000. M represents the DNA marker(/HindIII+ X174/HincII). The bands for the PCR products are schematically shown. (C) Poly (A)+RNA was extracted from the fat body. Upper lanes: these RNAs were reverse-transcribed with random hexamer, and the cDNAs were PCR-amplified with primers TGM2F and TGM2R. Lower lanes: these RNAs were reverse-transcribed with random hexamer, and the cDNAs were PCR-amplified with primers BmA3QPCR1F and BmA3QPCR1R. Resulting products were separated on a 1% agarose gel and visualized with SYBR Green I (Molecular Probes) at a dilution of 1: 10,000 (upper lanes) and visualized with ethidium bromide (lower lanes). M represents the DNA marker (/HindIII+ X174/HincII). The bands for the PCR products are schematically shown.